1. Field Of The Invention
Reclamation of solid refuse is playing an increasingly important role in modern waste disposal systems. Beyond the obvious ecological advantages of salvaging recyclable materials, the monetary value of certain commonly discarded materials makes solid waste reclamation economically feasible. However, such a reclamation system requires hand or other sorting of the desired valuable materials, such as aluminum, ferrous metals, and the like, from the undesired materials.
The sorting operation is often located at the site of a landfill. Typically, solid waste is dumped onto a conveyor which transports the refuse through a sorting area. The desired materials are removed from the conveyor and placed in appropriate storage areas while the undesired materials remain on the conveyor and are delivered to the landfill pit. A major problem encountered in these sorting operations is that much of the refuse to be sorted is packaged in standard plastic or paper refuse carrier bags. The openings of such carrier bags are tightly closed, usually by a wire or plastic tie member or simply by knotting the open end. In any event, the carrier bags are designed to resist any attempt to tear or otherwise open them to expose the contents therein. Such carrier bags, therefore, interpose a considerable time and energy-consuming delay in a reclamation operation which relies upon the rapid and efficient sorting of materials for economic feasibility. Accordingly, it would be desirable to provide a simple and efficient means for opening carrier bags containing refuse to expose the contents therein.
2. Description of The Prior Art
The common method of opening carrier bags is simply to cut the bags open with a knife blade of some sort. In some instances, a person is provided on the conveyor line to cut open the bags and expose the refuse therein before it reached the sorting area. However, the requirement of an additional person in the reclamation system decreases the efficiency of the operation. In other instances, a machine is provided with cutting blades to chop open the carrier bags. Such cutting machines suffer from frequent breakdowns caused by the striking of the cutting blade against unyielding solid objects within the carrier bag. Trommels and shredders have also been utilized in the past to tear open carrier bags. However, such devices destroy the original shape of the articles of refuse contained in the carrier bags, making sorting of the articles quite difficult.
U.S. Pat. No. 3,074,534 to Thiele discloses a material handling apparatus for distributing livestock feed to a plurality of spaced feeding bins. The apparatus includes a feed receiving hopper, a cylindrical auger tube extending outwardly from the hopper above the bins and having discharge openings in the lower side thereof above each bin, and a conveying auger extending from the hoppers through the tube. Rotary driving means rotate the auger to displace material from the hopper through the auger tube to each of the discharge openings.
U.S. Pat. No. 3,176,832 to Wilkes discloses a bulk feeder having an elongated auger tube assembly with a continuous slot extending from one end to the other end with a lower lip over which material may be discharged. An auger flighting is provided within the tube assembly. Track structures extend around the tube assembly and outwardly thereof. Each of the track structures has a continuous outer track spaced from the tube assembly and radial flange extending inwardly from the track and fixed to the surface of the tube assembly. The radial flange has a radially outward recess formed across the expanse of the slot.
U.S. Pat. No. 3,232,419 to Rasmussen discloses a screw conveyor including a casing having an inlet open to a region at one pressure and an outlet open to a region at a different pressure. A shaft extends through the casing from the inlet to the outlet. A first screw impeller on the shaft advances material through the casing from the inlet towards the outlet. Means are provided for defining a chamber above and open to the casing between the inlet and the outlet. A second screw impeller on the shaft of a hand opposite to that of the first impeller is provided to backup the material to form a pile of material in the chamber thereby sealing the casing at the upstream side of the chamber. The second screw impeller has an inclined surface down which the material slides into the casing near the downstream side of the chamber.
U.S. Pat. No. 3,312,329 to Hokana discloses a feed processing assembly including a gravity feed tank having a least one separator arranged longitudinally of the gravity feed tank to divide it into a plurality of elongated compartments. Each of the compartments has an inclined bottom terminating in a gate means. The gate means leads to a receiving area for dispensing the feed. An enclosed screw conveyor is positioned substantially longitudinally and centrally of the gravity feed tank. One end of the conveyor extends beyond the gravity feed tank to the receiving area. The conveyor is open at one end to collect and remove material from the area to a processing mill.
U.S. Pat. No. 4,310,089 to Bondeson et al. discloses a conveyor for transporting bags of refuse including a feed tube in which bags of refuse are introduced and transported from one end to the other and a feed screw in the tube for driving the bags of refuse through the tube. The feed screw is constructed as a helix forming successive spaced flanges. The pitch of the helix is such that the space between successive flanges will accommodate a bag of refuse of predetermined maximum overall size. The feed screw is eccentrically journalled in the feed tube and is in tangential contact at the bottom thereof.